[PATCH v4 6/8] crypto: x86/aesni: Use new glue function macros

From: Kees Cook
Date: Mon Nov 11 2019 - 16:46:19 EST


Convert to function declaration macros from function prototype casts to
avoid triggering Control-Flow Integrity checks during indirect function
calls.

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
arch/x86/crypto/aesni-intel_glue.c | 31 ++++++++++--------------------
1 file changed, 10 insertions(+), 21 deletions(-)

diff --git a/arch/x86/crypto/aesni-intel_glue.c b/arch/x86/crypto/aesni-intel_glue.c
index 3e707e81afdb..e1072ea0a4fa 100644
--- a/arch/x86/crypto/aesni-intel_glue.c
+++ b/arch/x86/crypto/aesni-intel_glue.c
@@ -33,9 +33,7 @@
#include <crypto/internal/skcipher.h>
#include <linux/workqueue.h>
#include <linux/spinlock.h>
-#ifdef CONFIG_X86_64
#include <asm/crypto/glue_helper.h>
-#endif


#define AESNI_ALIGN 16
@@ -83,10 +81,8 @@ struct gcm_context_data {

asmlinkage int aesni_set_key(struct crypto_aes_ctx *ctx, const u8 *in_key,
unsigned int key_len);
-asmlinkage void aesni_enc(struct crypto_aes_ctx *ctx, u8 *out,
- const u8 *in);
-asmlinkage void aesni_dec(struct crypto_aes_ctx *ctx, u8 *out,
- const u8 *in);
+CRYPTO_FUNC(aesni_enc);
+CRYPTO_FUNC(aesni_dec);
asmlinkage void aesni_ecb_enc(struct crypto_aes_ctx *ctx, u8 *out,
const u8 *in, unsigned int len);
asmlinkage void aesni_ecb_dec(struct crypto_aes_ctx *ctx, u8 *out,
@@ -550,19 +546,14 @@ static int xts_aesni_setkey(struct crypto_skcipher *tfm, const u8 *key,
}


-static void aesni_xts_tweak(void *ctx, u8 *out, const u8 *in)
-{
- aesni_enc(ctx, out, in);
-}
-
static void aesni_xts_enc(void *ctx, u128 *dst, const u128 *src, le128 *iv)
{
- glue_xts_crypt_128bit_one(ctx, dst, src, iv, GLUE_FUNC_CAST(aesni_enc));
+ glue_xts_crypt_128bit_one(ctx, dst, src, iv, aesni_enc);
}

static void aesni_xts_dec(void *ctx, u128 *dst, const u128 *src, le128 *iv)
{
- glue_xts_crypt_128bit_one(ctx, dst, src, iv, GLUE_FUNC_CAST(aesni_dec));
+ glue_xts_crypt_128bit_one(ctx, dst, src, iv, aesni_dec);
}

static void aesni_xts_enc8(void *ctx, u128 *dst, const u128 *src, le128 *iv)
@@ -581,10 +572,10 @@ static const struct common_glue_ctx aesni_enc_xts = {

.funcs = { {
.num_blocks = 8,
- .fn_u = { .xts = GLUE_XTS_FUNC_CAST(aesni_xts_enc8) }
+ .fn_u = { .xts = aesni_xts_enc8 }
}, {
.num_blocks = 1,
- .fn_u = { .xts = GLUE_XTS_FUNC_CAST(aesni_xts_enc) }
+ .fn_u = { .xts = aesni_xts_enc }
} }
};

@@ -594,10 +585,10 @@ static const struct common_glue_ctx aesni_dec_xts = {

.funcs = { {
.num_blocks = 8,
- .fn_u = { .xts = GLUE_XTS_FUNC_CAST(aesni_xts_dec8) }
+ .fn_u = { .xts = aesni_xts_dec8 }
}, {
.num_blocks = 1,
- .fn_u = { .xts = GLUE_XTS_FUNC_CAST(aesni_xts_dec) }
+ .fn_u = { .xts = aesni_xts_dec }
} }
};

@@ -606,8 +597,7 @@ static int xts_encrypt(struct skcipher_request *req)
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct aesni_xts_ctx *ctx = crypto_skcipher_ctx(tfm);

- return glue_xts_req_128bit(&aesni_enc_xts, req,
- XTS_TWEAK_CAST(aesni_xts_tweak),
+ return glue_xts_req_128bit(&aesni_enc_xts, req, aesni_enc,
aes_ctx(ctx->raw_tweak_ctx),
aes_ctx(ctx->raw_crypt_ctx),
false);
@@ -618,8 +608,7 @@ static int xts_decrypt(struct skcipher_request *req)
struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
struct aesni_xts_ctx *ctx = crypto_skcipher_ctx(tfm);

- return glue_xts_req_128bit(&aesni_dec_xts, req,
- XTS_TWEAK_CAST(aesni_xts_tweak),
+ return glue_xts_req_128bit(&aesni_dec_xts, req, aesni_enc,
aes_ctx(ctx->raw_tweak_ctx),
aes_ctx(ctx->raw_crypt_ctx),
true);
--
2.17.1